基于平板计数的类球红细菌测量方法研究

类球红细菌是产辅酶Q₁₀的主要微生物之一，定量检测类球红细菌活菌数对优化类球红细菌的发酵条件具有重要意义。通过对接种方式、接种量、培养基种类以及培养温度进行比较研究，对类球红细菌的平板计数法进行优化，并对优化后的平板计数法进行协同实验验证和不确定度分析。平板计数法最终优化结果为：接种方式为涂布法，接种量为50μL,培养基为营养琼脂，培养温度为32℃;该方法重复性和再现性均较好，室内重复性相对标准偏差为6.0%,室间相对标准偏差为16.4%。所优化方法的相对扩展不确定度为9.2%(k=2),适用于类球红细菌定量测量。     

枯草芽孢杆菌黑色变种芽孢测量方法研究

枯草芽孢杆菌黑色变种芽孢是生物防护和灭菌效果评价的重要指示微生物,其量值准确可以保证评价的有效性和可比性。对枯草芽孢杆菌涂布平板法进行了方法验证和协同实验验证以及不确定度分析。结果显示,当平板上的菌落数在30～300CFU之间时,该方法重复性和再现性均较好,室内重复性相对标准偏差为10.0%,室间相对标准偏差为14.1%。经统计分析,胰蛋白胨大豆琼脂培养基平板涂布法相对扩展不确定度为12.0%(k=2),适用于枯草芽孢杆菌黑色变种芽孢定量测量,对于人员防护装备防护性能评价、消毒剂检测及灭菌质量控制具有重要意义。     

噬菌体ΦX174标准物质定值方法研究

采用国际标准ISO 16604中噬菌体ΦX174的双层琼脂计数方法作为噬菌体ΦX174标准物质定值方法,针对该方法进行了方法验证和协同实验验证以及不确定度分析。结果显示,该方法重复性和复现性均较好,室内重复性相对标准偏差为10.18%,室间相对标准偏差为14.58%。经统计分析,双层琼脂计数法相对扩展不确定度为12.44%,适用于噬菌体ΦX174标准物质的定值,对于人员防护装备防护性能评价具有重要意义。     

阴沟肠杆菌定量标准物质的研制

采用真空冷冻干燥法和滤膜法定值技术,研制了球状的阴沟肠杆菌定量标准物质。经保护剂配方及冻干程序参数优化后,阴沟肠杆菌的平均存活率达51%,形状均匀一致、外观光滑无塌陷,能完全复水速溶。通过结晶紫中性胆盐琼脂培养基平板计数法考察均匀性和稳定性,证明该标准物质均匀性良好,-80 ℃至少可稳定保存6个月。该标准物质由6家实验室采用滤膜法联合定值,经不确定度评定,标称值为（2.0±0.1）log10 (cfu/瓶),相对扩展不确定度为10%(k=2)。标准物质中阴沟肠杆菌活菌数含量水平为10² cfu/瓶,可以直接溶解使用,无需稀释,使用方便,同时减少了测量不确定度来源。     

酸性橙II纯度标准物质的研制

质量平衡法是确定有机类标准物质纯度的经典方法,利用质量平衡法研制了GBW(E)100373酸性橙Ⅱ纯度标准物质,介绍了标准物质样品的制备、均匀性检验、稳定性检验、定值、不确定度评定及比对和验证等严格的研发程序。最终获得了纯度认定值为99.2%,相对扩展不确定度为1.0% (k=2)的酸性橙II纯度标准物质,可以在食品和化妆品分析中的仪器校准和方法评定等领域发挥重要作用。     

标准曲线配制对电感耦合等离子体质谱法测定饮用水中重金属元素的影响研究

采用容量法和称量法分别配制了ICP-MS法的标准工作曲线,并测定了生活饮用水中铅和镍的含量,对两种方法的不确定度进行评定。对不确定度的来源进行了全面分析,评定了各不确定度分量并合成了扩展不确定度。按照建立的不确定度评定方法得到容量法相对不确定度为urel(Pb)=2.8%,urel(Ni)=2.4%;称量法相对不确定度为urel(Pb)=1.6%,urel(Ni)=1.0%。所建立的不确定度评定程序适用于ICP-MS法测定饮用水中重金属元素含量的不确定度评定。通过比较两种方法的不确定度及相关分量贡献,从标准溶液配制的角度提出完善ICP-MS分析方法的途径,为加强饮用水中重金属检测、确保水质安全提供科学依据。     

气体标准物质研制中标气样品的均匀性和稳定性判定方法研讨

用标准偏差法和趋势分析法对标气样品的均匀性和稳定性的判定作了比较,结果一致;合成的相对扩展不确定度吻合,可以认为两种方法在标气样品的均匀性和稳定性的判定具有相同的效果。     

新一代锌固定点容器的研制

新一代锌固定点容器在中国计量科学研究院最新建立的灌注系统上完成灌注,采用了石墨温度计阱平衡重物下沉法及新的焊接工艺.该固定点容器温坪可持续时间超过16小时,前50%温坪变化了0.17 mK.用两支标准铂电阻温度计验证其复现性,6次测量结果标准偏差分别为0.18和0.16 mK.经过不确定度评定,该固定点容器扩展不确定度为0.64 mK.     

莫来石导热系数的测量不确定度评定及验证

使用防护热板法测定莫来石试样在各温度下的导热系数,分析了测量不确定度的来源、并根据ISO/IEC 98-3:2008中的基本方法(GUM法)计算了各标准不确定度分量、合成标准不确定度及扩展不确定度,并确定了各分量的影响大小,最后采用蒙特卡洛法(MCM)对测量不确定度的评定结果进行了比较验证。结果表明:在150~500℃莫来石导热系数测定结果的相对扩展不确定度(k=2)小于4%;板平面内温度分布均匀性在各影响因素中占据主导地位,对导热系数测定结果的影响最大;150℃时的评定结果通过MCM验证,可用GUM法来评定莫来石导热系数的测量不确定度。     

雷氏夹膨胀测定仪测得值的不确定度评定

本文简述了雷氏夹膨胀测定仪的工作原理,依据JJG (交通) 093-2009《雷氏夹及雷氏夹膨胀测定仪》检定规程,结合具体检定过程,对雷氏夹膨胀测定仪的检定项目建立了测量模型,分析了测得值的标准不确定度分量来源,运用不确定度评定与表示方法,给出了雷氏夹膨胀测定仪测得值不确定度评定报告。     

Development and validation of a near-infrared method for the quantitation of caffeine in intact single tablets

A near-infrared spectroscopic method was developed and validated for determining the caffeine concentration of single and intact tablets in a Finnish pharmaceutical product containing 58.82% (m/m) caffeine.The spectral region of interest contained a total of 474 data points. The second derivative of Savitsky-Golay, a standard normal variate, and mean centering were used as spectral preprocessing options. The feasibility study showed nonuniformity of caffeine repartition within each tablet. Thus, spectra were recorded from both faces of the tablets, and the analysis result for a single tablet was reported as the average of both face determinations. Precision of the method was validated because the relative standard deviations from repeatability and intermediate precision tests were below 0.75% (m/m). Accuracy validation proved that the NIR results were not significantly different (P = 0.09, n = 12) from the results obtained with the reference HPLC method. The limit of quantification for caffeine was 13.7% (m/m) in the tablets. The method was found to be unaffected by NIR source replacement, but the repeatability of the results was affected if the sample holder was not placed in the correct position in the light beam. Routine NIR analysis of caffeine in tablet form was found to be more flexible and much faster than that performed with the HPLC method.     

基于GC-MS法测定纸质包装中4种二苯甲酮类物质

目的 利用气相色谱-质谱联用(GC-MS)法进行纸质包装中4种二苯甲酮类物质的测定.方法 优化超声提取纸质包装材料中二苯甲酮类光引发剂的方法,提取液使用GC-MS进行分析,采用全扫描和离子扫描方式确认每个物质的定性和定量离子.验证该方法的检出限、定量限、线性范围、相对标准偏差和回收率后用于实际样品的分析.结果 得到优化后的超声提取条件,乙腈作为提取溶剂,超声提取2次,每次提取时间为20 min.4种二苯甲酮类物质的检出限为0.01～0.05 mg/L,定量限为0.02～0.10 mg/L,标准添加实验的结果显示,相对标准偏差为2.0％～2.6％,回收率为98％～105％.结论 该方法检出限和定量限均较低,精密度和准确度较高,适合于实际纸质包装样品中4种二苯甲酮类物质的分析.     

旋翼天平原位校准的不确定度分析

旋翼天平原位校准中,校准不确定度是最核心的技术指标.根据实际工况环境,研究了原位校准方法,研制了原位校准装置,重点介绍了机械设计结构,梳理和明确了不确定度来源,最后完成了旋翼天平的首次原位校准测试工作,并依照规范的方法进行了原位校准不确定度评价,结果表明:校准装置性能达标,各力值分量相对校准不确定度均优于0.1％,各力...     

High Accuracy Measurement of Aperture Area Relative to a Standard Known Aperture

Precise knowledge of the area of apertures used in high precision radiometry is extremely important. A method is presented here for the determination of the area of round and irregularly shaped apertures by comparison to a standard aperture which has been measured by other means to high accuracy. The method presented here is quick and has no physical contact with the fragile edge of the aperture opening. Total flux transfer methods are used in the area determination with total relative standard uncertainty of 0.033 % for 2 mm to 25 mm mean diameter apertures not including the area uncertainty of the standard aperture used. Currently the relative standard uncertainty in the area measurement for the stadard aperture is 0.022 %. The worst case relative standard uncertainty of the transfer measurement is 0.04 % including the uncertainty of the standard aperture area.     

Evaluation of a Rapidly Disintegrating, Moisture Resistant Lacquer Film Coating

Simplex optimization was used during the development of a rapidly disintegrating, moisture resistant lacquer film coating. A hygroscopic aniomic exchange resin with the capability of adsorbing four to five times its weight in water was used as the model drug. The coating variables investigated included levels of magenesium stearate, talc, hydroxypropylmethylcelluslose (5 cps), polyethylene glycol 8000, Opaspray, and Eudragit E30D. Response parameters monitored included disintegration time, percent weight gain after 48 hours in a 30 deg C 75% relative humidity chamber and physical appearance. The effect of the core tablet on the performance of the coated tablet was also investigated. This study illustrates the use of the simplex design in the development of a film coating formula. It also examines the interaction between the core tablet and the film coating.     

The Development of a Blend-Sampling Technique to Assess the Uniformity of a Powder Mixture

This article discusses the challenges overcome during the development of a blendsampling technique and the successful validation of the blending operation for a tablet dosage form containing 2% active ingredient. Content uniformity results are discussed for three pilot-scale (15-kg) and seven commercial-scale (150-kg) batches of tablets. Blend and core content uniformity data from the pilot-scale batches were acceptable. For the initial commercial-scale batches, although the tablet core content uniformity data were acceptable, the blend uniformity results were poor. The blend data for these batches had very high mean values, but acceptable relative standard deviations (RSDs). This suggested that the drug was being preferentially sampled by the thief, but in a consistent, reproducible manner. Extensive testing was performed on a commercial-scale development batch to identify potential causes of sampling error. The results of this testing helped define the blend-sampling technique and strategy used to validate the mixing operation.     

The Development of a Blend-Sampling Technique to Assess the Uniformity of a Powder Mixture

This article discusses the challenges overcome during the development of a blendsampling technique and the successful validation of the blending operation for a tablet dosage form containing 2% active ingredient. Content uniformity results are discussed for three pilot-scale (15-kg) and seven commercial-scale (150-kg) batches of tablets. Blend and core content uniformity data from the pilot-scale batches were acceptable. For the initial commercial-scale batches, although the tablet core content uniformity data were acceptable, the blend uniformity results were poor. The blend data for these batches had very high mean values, but acceptable relative standard deviations (RSDs). This suggested that the drug was being preferentially sampled by the thief, but in a consistent, reproducible manner. Extensive testing was performed on a commercial-scale development batch to identify potential causes of sampling error. The results of this testing helped define the blend-sampling technique and strategy used to validate the mixing operation.